External device identification method and apparatus in a device including a touch spot, and computer-readable recording mediums having recorded thereon programs for executing the external device identification method in a device including a touch spot

CROSS-REFERENCE TO RELATED PATENT APPLICATIONS

0001This application is a Continuation-In-Part of U.S. patent application Ser. No. 12/274,755, filed on Nov. 20, 2008, which is a Continuation-In-Part of U.S. application Ser. No. 12/133,812, filed on Jun. 5, 2008, which claims priority from Korean Patent Application No. 10-2007-0118531, filed on Nov. 20, 2007, and Korean Patent Application No. 10-2008-0091774, filed on Sep. 18, 2008, in the Korean Intellectual Property Office. The disclosure of each of the above-referenced applications is herein incorporated by reference in their entirety.

BACKGROUND

00021. Field

0003Methods, apparatuses, devices and computer readable recording mediums consistent with exemplary embodiments relate to an external device identification method and apparatus in a device including a touch spot, and a recording medium, and more particularly, to an external device identification method and apparatus in a device including a touch spot, and a recording medium whereby the device including a touch spot can identify an external device, and computer-readable recording medium having recorded thereon programs for executing the above method.

00042. Description of the Related Art

0005In order to technically implement a scenario in which a touch screen device and an external device interact with each other, the external device should be easily connectable to the touch screen device, and preferably the external device has to be connected in relation to coordinates on a graphic user interface (GUI) of the touch screen device.

0006Related art techniques for a display device to identify an external device include a radio frequency identification (RFID) scheme, a camera scheme, and a global positioning system (GPS) scheme. According to the RFID scheme, a tag reader is installed outside the display device and an RFID tag is attached to the external device in order to recognize an identification (ID) of the external device. According to the camera scheme, a camera is attached on or under a table display in order to recognize the position of the external device. According to the GPS scheme, the position of the external device is recognized using a GPS reception unit.

0007However, the position of the external device cannot be known according to the RFID scheme, a recognition rate is low and high processor performance is required due to image processing according to the camera scheme, and a position error and device complexity increase in a small space such as the display device according to the GPS scheme.

0008Moreover, when the size of a touch screen surface is small, the external device and the touch screen device have to easily interact with each other.

SUMMARY

0009Exemplary embodiments provide an external device identification method, an external device identification apparatus in order to connect a device including a touch spot with an external device by simple physical touching, and a computer-readable recording medium having recorded thereon a program for executing the external device identification method.

0010According to an aspect of an exemplary embodiment, there is provided an external device identification apparatus in a device including a touch spot. The apparatus includes a transmission unit that generates a first micro-current signal that is induced when a touch spot is touched by a human being and includes device information about the device including the touch spot, and propagates the first micro-current signal to an external device via a human being; a reception unit that receives a second micro-current signal including device information about the external device from the external device via the human being, and detects the device information of the external device from the second micro-current signal; and an identification unit that identifies the external device by using the device information of the external device, and connects the device including the touch spot to the external device through a communication channel.

0011The device may include another touch spot separate from the touch spot, and the reception unit may receive the second micro-current signal through the touch spot or the another touch spot.

0012The device may further include a physical operation button or a graphic user interface that displays an operation button, and the apparatus may further include an operation control unit that, at a time at which the physical operation button or the operation button displayed on the graphic user interface is touched by the human being, controls the transmission unit to generate the first micro-current signal and the reception unit to receive the second micro-current signal.

0013The touch spot may be a touch electrode or a capacitive button.

0014The touch electrode may be disposed to cover an upper portion of the physical operation button.

0015The device may include a display screen, and the touch electrode may be disposed on a surface of the device that is opposite from the surface of the display screen.

0016The capacitive button may be connected by a switch to the transmission unit, the reception unit, and the operation control unit in a time-divisional manner.

0017The transmission unit may include a signal generation unit that generates a binary signal including device information about the device including the touch spot; and a modulation unit that generates the first micro-current signal by modulating the binary signal, and outputs the first micro-current signal to the touch spot.

0018The reception unit may include a filter unit that filters a noise component from the second micro-current signal; an amplification unit that amplifies the filtered second micro-current signal output from the filter unit; and a demodulation unit that detects the binary signal including device information about the external device by demodulating the signal output from the amplification unit.

0019The device including the touch spot may be a remote controller for controlling the external device remotely.

0020According to an aspect of another exemplary embodiment, there is provided an external device identification method in a device including a touch spot. The method includes generating a first micro-current signal that is induced at a time at which a touch spot is touched by a human being and includes device information about the device including the touch spot; propagating the first micro-current signal to an external device via the human being; receiving a second micro-current signal including device information about the external device from the external device via the human being; detecting the device information about the external device from the second micro-current signal; identifying the external device by using the device information about the external device; and connecting the device including the touch spot to the external device through a communication channel.

0021The device may include another touch spot that is separate from the touch spot, and the receiving of the second micro-current signal may include receiving the second micro-current signal through the touch spot or the another touch spot.

0022The device may include a physical operation button or graphic user interface, and the method may further include controlling the device to generate the first micro-current signal and to receive the second micro-current signal, at a time at which the physical operation button or an operation button displayed on the graphic user interface is touched by the human being.

0023The touch spot may be a touch electrode or a capacitive button.

0024The touch electrode may be disposed to cover an upper portion of the physical operation button.

0025The device may include a display screen, and the touch electrode may be disposed on a surface of the device that is opposite to the surface of the display screen.

0026The capacitive button may be used to propagate the first micro-current signal to the external device, to receive the second micro-current signal from the external device, and to control the generation of the first micro-current signal and receipt of the second micro-current signal in a time-divisional manner.

0027The propagating of the first micro-current signal may include generating a binary signal including device information about the device including the touch spot; and generating the first micro-current signal by modulating the binary signal and outputting the first micro-current signal to the touch spot.

0028The detecting of the device information about the external device may include removing a noise component from the second micro-current signal; amplifying the second micro-current signal from which the noise component is removed; and detecting a binary signal including device information about the external device by demodulating the amplified signal.

0029The device including the touch spot may be a remote controller for controlling the external device remotely.

0030According to an aspect of another exemplary embodiment, there is provided a computer readable recording medium having embodied thereon a program for executing an external device identification method in a device including a touch spot. The method includes generating a first micro-current signal that is induced when a touch spot is touched by a human being and includes device information about the device including the touch spot, and propagating the first micro-current signal to an external device via the human being; receiving a second micro-current signal including device information about the external device from the external device via the human being, and detecting the device information about the external device from the second micro-current signal; and identifying the external device by using the device information about the external device, and connecting the device including the touch spot to the external device through a communication channel.

0031According to an aspect of another exemplary embodiment, there is provided a device comprising a touch spot; a transmission unit that generates a first micro-current signal that is induced at a time at which the touch spot is touched by a human being and includes device information about the device, and propagates the first micro-current signal to an external device via the human being; a reception unit that receives a second micro-current signal including device information about the external device from the external device via the human being, and detects the device information of the external device from the second micro-current signal; and an identification unit that identifies the external device by using the device information of the external device; and connects the device to the external device through a communication channel other than the human being.

BRIEF DESCRIPTION OF THE DRAWINGS

0032The above and other aspects will become more apparent by describing in detail exemplary embodiments with reference to the attached drawings in which:

0033<figref idref="DRAWINGS">FIG. 1</figref> illustrates a touch-screen based device identification system according to a first exemplary embodiment;

0034<figref idref="DRAWINGS">FIG. 2</figref> illustrates a touch-screen based device identification system according to a second exemplary embodiment;

0035<figref idref="DRAWINGS">FIG. 3</figref> illustrates a touch-screen based device identification system according to a third exemplary embodiment;

0036<figref idref="DRAWINGS">FIG. 4</figref> is a block diagram of a touch-screen based device identification system according to an exemplary embodiment;

0037<figref idref="DRAWINGS">FIG. 5</figref> is a flowchart illustrating a touch-screen based device identification method for a touch screen device according to an exemplary embodiment;

0038<figref idref="DRAWINGS">FIG. 6</figref> is a flowchart illustrating a device information provision method for an external device according to another exemplary embodiment;

0039<figref idref="DRAWINGS">FIG. 7</figref> illustrates a touch-screen based device identification system according to a fourth exemplary embodiment;

0040<figref idref="DRAWINGS">FIG. 8</figref> is a block diagram of an external device identification system according to an exemplary embodiment;

0041<figref idref="DRAWINGS">FIGS. 9A</figref>, <b>9</b>B, and <b>9</b>C are exemplary views showing touch spots, according to exemplary embodiments;

0042<figref idref="DRAWINGS">FIG. 10A</figref> is a diagram showing an internal structure of a transmission unit of <figref idref="DRAWINGS">FIG. 8</figref>;

0043<figref idref="DRAWINGS">FIG. 10B</figref> is a diagram showing an internal structure of a reception unit of <figref idref="DRAWINGS">FIG. 8</figref>; and

0044<figref idref="DRAWINGS">FIG. 11</figref> is a flowchart illustrating an external device identification method in a device including a touch spot according to another exemplary embodiment.

DETAILED DESCRIPTION

0045Hereinafter, exemplary embodiments will be described in detail with reference to the accompanying drawings. It should be noted that like reference numerals refer to like elements illustrated in one or more of the drawings. In the following description, detailed descriptions of known functions and configurations incorporated herein will be omitted for conciseness and clarity.

0046<figref idref="DRAWINGS">FIG. 1</figref> illustrates a touch-screen based device identification system according to a first exemplary embodiment.

0047Referring to <figref idref="DRAWINGS">FIG. 1</figref>, the touch-screen based device identification system includes an external device <b>110</b> and a touch screen device <b>120</b>. The external device <b>110</b> and the touch screen device <b>120</b> are connected with each other through a communication channel <b>130</b>. It is assumed that a person <b>140</b> touches a touch screen surface of the touch screen device <b>120</b> with one hand while holding the external device <b>110</b> with the other hand. In another exemplary embodiment, a person <b>140</b> may touch a touch screen surface of the touch screen device <b>120</b> using a conductive medium such as metal.

0048The external device <b>110</b> is a consumer electronics (CE) device capable of communicating with another device through the communication channel <b>130</b>. The external device <b>110</b> may be a cellular phone, a digital camera, a camcorder, a personal digital assistant (PDA), an MP3 player, or a portable multimedia player (PMP). In another exemplary embodiment, the external device <b>110</b> may be another touch screen device in addition to the touch screen device <b>120</b>.

0049A signal induced by touching a touch screen surface of the touch screen device <b>120</b> propagates to the external device <b>110</b> via the person <b>140</b>. A detection unit <b>150</b> of the external device <b>110</b> detects a scan frequency component from the signal induced by a touch of the touch screen surface in the touch screen device <b>120</b>.

0050Upon detection of the scan frequency component, the external device <b>110</b> generates information about the detected scan frequency component and ID device information of the external device <b>110</b> and transmits the generated information and ID information to the touch screen device <b>120</b> through the communication channel <b>130</b>. The external device <b>110</b> may include a band pass filter unit that detects a micro-current signal that is induced from the touch screen surface and is received via the person <b>140</b>. The micro-current signal propagating to the external device <b>110</b> is detected after passing through the band pass filter unit of the external device <b>110</b>.

0051The touch screen device <b>120</b> is a device capable of performing specific processing by recognizing the position of a character or a particular position on the touch screen surface, which is touched by a human hand, without using a keyboard. A touch-screen scheme may be classified into different types including, for example, a resistive film type, a static capacitance type, etc. According to the static capacitance type, the touch screen surface is electrically charged, sensors are installed along the circumference of the touch screen surface, and a touched position is recognized by sensing the amount of electric charges lost by a touch.

0052Herein, the touch screen device <b>120</b> may be adapted by the static capacitance type. According to the static capacitance type, the touch screen device <b>120</b> performs a periodic scan in order to sense a touch. However, the touch screen device <b>120</b> is not limited to the static capacitance type, and may include all kinds of devices in which micro-current signals including a certain frequency (for example, scan frequency) are induced when the touch screen surface is touched.

0053According to the static capacitance type, the touch screen device <b>120</b> performs the scanning operation regularly to sense the touch. Thus, when the person <b>140</b> touches the touch screen surface of the touch screen device <b>120</b> with one hand while holding the external device <b>110</b> with the other hand, a micro-current including a particular frequency, e.g., a scan frequency, is induced by touching the touch screen surface. A micro-current signal including a scan frequency component, which is induced by touching the touch screen surface, propagates to the external device <b>110</b> via the person <b>140</b>.

0054The touch screen device <b>120</b> also receives information about the scan frequency component detected by the detection unit <b>150</b> and an ID of the external device <b>110</b> from the external device <b>110</b> through the communication channel <b>130</b>. The touch screen device <b>120</b> recognizes that the touch screen device <b>120</b> is connected with the external device <b>110</b> via the person <b>140</b> by using the information about the detected scan frequency component and the ID of the external device <b>110</b>, which are received from the external device <b>110</b>.

0055In addition, in order to distinguish the touch screen device <b>120</b> that propagates the induced signal from a plurality of touch screen devices, the external device <b>110</b> may broadcast confirmation request signals, which identify whether the touch screen surface of the touch screen device <b>120</b> is touched, to a plurality of touch screen devices through communication channels. Then, the touch screen device <b>120</b>, which propagates the signal induced by touching the touch screen surface to the external device <b>110</b>, may transmit a confirmation response signal that notifies about the touch to the touch screen surface to the external device <b>110</b> through the communication channel <b>130</b>. The other touch screen devices, touch screen surfaces of which are not touched, may not transmit the confirmation response signal to the external device <b>110</b>.

0056The communication channel <b>130</b> is a data transmission/reception path that is previously established before the person <b>140</b> touches the external device <b>110</b> and the touch screen device <b>120</b>. Thus, the external device <b>110</b> and the touch screen device <b>120</b> are in a state in which data can be exchanged through the communication channel <b>130</b> whenever needed.

0057The communication channel <b>130</b> is a local connection using a plug-and-play (PnP) protocol such as a universal PnP (UPnP) protocol and may be a wired or wireless channel. In addition, the communication channel <b>130</b> may be a wireless communication channel, and the wireless communication channel may include one or more of a wireless local area network (LAN), a wireless internet platform for interoperability (WIPI), Bluetooth, infrared communication, near field communication (NFC), or Zigbee, etc.

0058In addition, the external device <b>110</b> exchanges information about the communication channel (for example, wireless communication channel) with the touch screen device <b>120</b>, and may communicate through the selected communication channel based on the exchanged information. For example, when the external device <b>110</b> or the touch screen device <b>120</b> includes a plurality of communication channels, the external device <b>110</b> notifies the touch screen device <b>120</b> of the communication channels included in the external device <b>110</b>, and the touch screen device <b>120</b> may select the appropriate communication channel by comparing the communication channels of the external device <b>110</b> with the communication channels of the touch screen device <b>120</b>.

0059The person <b>140</b> can cause the external device <b>110</b> and the touch screen <b>120</b> to interact with each other by touching the touch screen surface of the touch screen device <b>120</b> with one hand while holding the external device <b>110</b> with the other hand. Since a human body is composed mostly of water including salt, the human body generally has the characteristics of a conductor at tens of KHz. Thus, a micro-current signal may propagate between the external device <b>110</b> and the touch screen <b>120</b> via the body of the person <b>140</b> who touches the external device <b>110</b> and the touch screen <b>120</b>. In this state, the touch screen device <b>120</b> acts as if a position touched by the hand of the person <b>140</b> is touched by the external device <b>110</b> and can perform particular processing. That is, the touch screen device <b>120</b> calculates the first coordinates of the touched point on the touch screen surface, and then, maps the external device <b>110</b> to the first coordinates. Here, mapping allows various applications to be executed as if the external device <b>110</b> touches the first coordinates.

0060In addition, when the external device <b>110</b> stores personal information or verification information (hereinafter, referred to as ‘user verification information’), services that allow the external device to access the touch screen device <b>120</b> or allow the external device to access the object displayed on the first coordinates of the touch screen device <b>120</b> can be provided using the user verification information.

0061In addition, as described above, the external device <b>110</b> may be another touch screen device in addition to the touch screen device <b>120</b>.

0062<figref idref="DRAWINGS">FIG. 7</figref> illustrates that the external device <b>110</b> may be another touch screen device. Referring to <figref idref="DRAWINGS">FIG. 7</figref>, processes for a touch screen device A <b>710</b> to identify a touch screen device B <b>730</b> via person <b>760</b> (or the opposite direction) are similar to those of the exemplary embodiment shown in <figref idref="DRAWINGS">FIG. 1</figref>. However, the touch screen devices A and B <b>710</b> and <b>730</b> may include detection units for detecting signals that are induced on touch screen surfaces of the counterpart touch screen devices <b>710</b> or <b>730</b> and are propagated. The detection units may be installed in the touch screen surface or on a position separated from the touch screen surface. The detection of the induced signals has been described already with reference to <figref idref="DRAWINGS">FIG. 1</figref>, and thus, detailed descriptions thereof are omitted.

0063The touch screen device A <b>710</b> calculates first coordinates X <b>720</b> that represent touched location on the touch screen surface of the touch screen device A <b>710</b>, and the touch screen device B <b>730</b> calculates second coordinates Y <b>740</b> that represent touched location on the touch screen surface of the touch screen device B <b>730</b>. After that, the touch screen devices A and B <b>710</b> and <b>730</b> may perform the mapping operation of the first and second coordinates X <b>720</b> and Y <b>740</b> through a communication channel <b>750</b>. Then, the touch screen devices A <b>710</b> and B <b>730</b> may execute an application service that links the first coordinates X <b>720</b> with the second coordinates Y <b>740</b> based on a result of the mapping operation. Through the above linkage between the coordinates, application services according to states of the touch screen devices and intention of the user can be provided.

0064For example, the touch screen device A <b>710</b> may transmit a control signal for allowing the object displayed on the first coordinates X <b>720</b> of the touch screen device A <b>710</b> (for example, icons, characters, products, or colors) to be displayed on the second coordinates Y <b>740</b> of the touch screen device <b>730</b> to the touch screen device B <b>730</b>, or receives the control signal from the touch screen device B <b>730</b>. For example, the color represented on the first coordinates X <b>720</b> may be equally displayed on the second coordinates Y <b>740</b>, and the product displayed on the first coordinates X <b>720</b> may be moved to the second coordinates Y <b>740</b>. On the other hand, the color represented on the second coordinates Y <b>740</b> may be equally displayed on the first coordinates X <b>720</b>, and the product displayed on the second coordinates Y <b>740</b> may be moved to the first coordinates X <b>720</b>.

0065Otherwise, a user interface such as a pop-up menu may be displayed in the touch screen devices, and thus, the user of the touch screen device A <b>710</b> or the touch screen device B <b>730</b> may select one of a plurality of services, coordinates of which can be linked with each other.

0066<figref idref="DRAWINGS">FIG. 2</figref> illustrates a touch-screen based device identification system according to a second exemplary embodiment.

0067An external device <b>210</b>, a communication channel <b>230</b>, a person <b>240</b>, and a reception unit <b>250</b>, which are illustrated in <figref idref="DRAWINGS">FIG. 2</figref>, operate in the same manner, respectively, as the external device <b>110</b>, the communication channel <b>130</b>, the person <b>140</b>, and the detection unit <b>150</b>, which are illustrated in <figref idref="DRAWINGS">FIG. 1</figref>, and thus will not be described again.

0068While the touch screen device <b>120</b> illustrated in <figref idref="DRAWINGS">FIG. 1</figref> operates by touching the touch screen surface, a touch screen device <b>220</b> illustrated in <figref idref="DRAWINGS">FIG. 2</figref> operates by touching one of touch spots <b>260</b> installed along the circumference of the touch screen device <b>220</b>. In other words, the touch screen <b>220</b> illustrated in <figref idref="DRAWINGS">FIG. 2</figref> operates by a touch to the touch spot <b>260</b> instead of to the touch screen surface.

0069The person <b>240</b> indicates a particular position on the touch screen surface by touching the touch spot <b>260</b> in order to cause the touch screen device <b>220</b> to perform particular processing. The touch spot <b>260</b> is designed so that a micro-current having a scan frequency component can flow through the touch spot <b>260</b>. Thus, once the person <b>240</b> touches the touch spot <b>260</b>, a micro-current signal propagates to the external device <b>210</b> via the person <b>240</b>. The touch screen device <b>220</b> receives information about the scan frequency component and an ID of the external device <b>210</b> from the external device <b>210</b>.

0070Consequently, if the person <b>240</b> touches the touch spot <b>260</b> of the touch screen device <b>220</b> with one hand, the touch screen device <b>220</b> can recognize that the touch screen device <b>220</b> is connected with the external device <b>210</b> the person <b>240</b> holds with the other hand.

0071<figref idref="DRAWINGS">FIG. 3</figref> illustrates a touch-screen based device identification system according to a third exemplary embodiment, in which there exists a plurality of external devices <b>310</b> and <b>330</b> or a plurality of touch screen devices <b>315</b> and <b>335</b>.

0072For example, it is assumed that a person A <b>320</b> holds an external device A <b>310</b> with one hand and touches a touch screen device A <b>315</b> with the other hand. It is also assumed that a person B <b>340</b> holds an external device B <b>330</b> with one hand and touches a touch screen device B <b>335</b> with the other hand. If the person A <b>320</b> and the person B <b>340</b> touch the touch screen device A <b>315</b> and the touch screen device B <b>335</b>, respectively, at almost the same time; the external devices A <b>310</b> and B <b>330</b> transmit information about scan frequency components and an ID of the external devices <b>310</b> and <b>320</b> to the touch screen device A <b>315</b> and the touch screen device B <b>335</b> through communication channels <b>350</b> and <b>360</b> and communication channels <b>355</b> and <b>365</b>, respectively. However, if the scan frequencies of micro-current signals induced in the touch screen devices A <b>315</b> and B <b>335</b> are the same as each other, the touch screen device A <b>315</b> or B <b>335</b> cannot recognize which one of the external devices A <b>310</b> and B <b>330</b> it is connected with.

0073In this case, the touch screen device A <b>315</b> or B <b>335</b> may be designed in such a way as to change a scan frequency of a micro-current signal induced by touching a touch screen surface. For example, when the touch screen device A <b>315</b> or B <b>335</b> receives scan frequency information and an ID from the plurality of external devices <b>310</b> and <b>330</b> within a predetermined period of time, the touch screen device A <b>315</b> or B <b>335</b> temporarily changes a scan frequency. The touch screen device A <b>315</b> or B <b>335</b> then receives scan frequency information corresponding to the changed scan frequency and an ID from the external devices <b>310</b> and <b>330</b> again. However, if both the touch screen device A <b>315</b> and the touch screen device B <b>335</b> change scan frequencies to another same frequency, the situation described above may occur again. This situation may be addressed by using a method of randomly determining a point of time for changing the scan frequency of the touch screen device A <b>315</b> or B <b>335</b> within a time range. However, in order to prevent the scan frequencies of the touch screen device A <b>315</b> and the touch screen device B <b>335</b> from being simultaneously changed to another same scan frequency, various methods may be used without being limited to the method described above.

0074Subsequently, the touch screen device A <b>315</b> or B <b>335</b> can identify the external device <b>310</b> or <b>330</b> connected with the touch screen device A <b>315</b> or B <b>335</b> by temporarily changing the scan frequency of the touch screen device A <b>315</b> or B <b>335</b>.

0075<figref idref="DRAWINGS">FIG. 4</figref> is a block diagram of a touch-screen based device identification system according to an exemplary embodiment.

0076Referring to <figref idref="DRAWINGS">FIG. 4</figref>, the touch-screen based device identification system includes an external device <b>410</b> and a touch screen device <b>450</b>. The external device <b>410</b> and the touch screen device <b>450</b> are coupled to each other through a communication channel <b>445</b>. A person <b>480</b> touches a detection unit <b>420</b> of the external device <b>410</b> with one hand and touches a touch sensing unit <b>455</b>, i.e., a touch screen surface, of the touch screen device <b>450</b> with the other hand.

0077The touch screen device <b>450</b> may include the touch sensing unit <b>455</b>, a reception unit <b>460</b>, and an identification unit <b>465</b>. The touch screen device <b>450</b> may further include a mapping unit <b>470</b> and a coordinates calculation unit <b>475</b>.

0078The touch sensing unit <b>455</b> generates a signal induced by touching the touch screen surface. The induced signal is a micro-current signal including a scan frequency component and propagates to the detection unit <b>420</b> of the external device <b>410</b> via the person <b>480</b>.

0079The touch sensing unit <b>455</b> can temporarily change a scan frequency of the micro-current signal induced by touching the touch screen surface.

0080The reception unit <b>460</b> receives information about the scan frequency component detected by the external device <b>410</b> and an ID of the external device <b>410</b> through the communication channel <b>445</b>.

0081The identification unit <b>465</b> identifies the external device <b>410</b> by using the information about the scan frequency component and the ID of the external device <b>410</b>, which are received by the reception unit <b>460</b>. For example, the identification unit <b>465</b> determines a scan frequency based on the information about the scan frequency component and compares the determined scan frequency with a scan frequency of the micro-current signal induced by a touch. If the determined scan frequency is the same as the scan frequency of the induced micro-current signal, the identification unit <b>465</b> determines that the touch screen device <b>450</b> is connected with the external device <b>410</b> having the received ID. Information about the scan frequency of the micro-current signal induced by a touch of the person <b>480</b> may be received from the touch sensing unit <b>455</b> or may be stored in the identification unit <b>465</b>.

0082The coordinates calculation unit <b>475</b> calculates coordinates of the touch screen surface touched (that is, first coordinates).

0083The mapping unit <b>470</b> maps the coordinates of the touch screen surface touched to the identified external device <b>410</b>. By doing so, the touch screen device <b>450</b> can act as if a position touched by a hand of the person <b>480</b> is touched using the external device <b>41</b> and can perform particular processing.

0084The external device <b>410</b> includes a detection unit <b>420</b>, an information generation unit <b>435</b>, and a transmission unit <b>440</b>. The external device <b>410</b> may be, for example, a cellular phone, a digital camera, a camcorder, a portable digital assistant (PDA), an MP3 player, or a portable media player (PMP).

0085The detection unit <b>420</b> detects a scan frequency component from a micro-current signal propagating from the touch sensing unit <b>455</b> and transmits the detected scan frequency component to the information generation unit <b>435</b>. For example, the detection unit <b>420</b> may include a band pass filter unit <b>425</b> and a tone decoder <b>430</b>. The band pass filter unit <b>425</b> performs band pass filtering on the micro-current signal by using a scan frequency as a center frequency. The tone decoder <b>430</b> performs tone-decoding on the band-pass filtered signal output from the band pass filter unit <b>425</b>. As a result, the detection unit <b>420</b> outputs information indicating whether the scan frequency component is included in the micro-current signal.

0086The information generation unit <b>435</b> generates information about the scan frequency component and ID device information of the external device <b>435</b> that has received the micro-current signal. The information generation unit <b>435</b> previously stores the ID device information of the external device <b>410</b>.

0087The transmission unit <b>440</b> transmits the information about the scan frequency component and the ID device information of the external device <b>410</b> to the reception unit <b>460</b> of the touch screen device <b>450</b> through the communication channel <b>445</b>.

0088In addition, the external device <b>410</b> may be another touch screen device in addition to the touch screen device <b>450</b>. In this case, the mapping unit <b>470</b> may map the second coordinates of the external device <b>410</b> to the first coordinates of the touch screen device <b>450</b>. The mapping unit <b>470</b> may perform the mapping operation through the communication channel <b>445</b>.

0089In addition, the mapping unit <b>470</b> may control a control signal, which allows the object displayed on the first coordinates to be displayed on the second coordinates, transmitted to the external device <b>410</b> or received from the external device <b>410</b>. Consequently, the external device <b>410</b> or the touch screen device <b>450</b> may execute various application services caused by the linkage between the first and second coordinates based on the mapping result.

0090The communication channel <b>445</b> may be a wired or wireless channel using a PnP protocol such as a UPnP protocol.

0091<figref idref="DRAWINGS">FIG. 8</figref> is a block diagram of an external device identification system according to another exemplary embodiment.

0092Referring to <figref idref="DRAWINGS">FIG. 8</figref>, the external device identification system includes a device A <b>810</b> and a device B <b>850</b>. The device A <b>810</b> and the device B <b>850</b> may be respectively portable mobile devices such as a mobile phone, a digital camera, a camcorder, a personal digital assistant (PDA), an MP3 player, or a personal multimedia player (PMP), etc. In addition, the device A <b>810</b> (or the device B <b>850</b>) may be a remote controller for controlling the device B <b>850</b> (or the device A <b>810</b>) remotely.

0093The device A <b>810</b> and the device B <b>850</b> are coupled to each other via a communication channel <b>870</b>. In addition, a person <b>880</b> touches a touch spot A <b>818</b> of the device A <b>810</b> with a finger or hand, and touches a touch spot B <b>858</b> of the device B <b>850</b> with another finger or hand.

0094The device A <b>810</b> includes a transmission unit A <b>812</b>, a reception unit A <b>814</b>, and an identification unit A <b>820</b>. In addition, the device A <b>810</b> may further include an operation control unit A <b>816</b>. Similarly, the device B <b>850</b> includes a transmission unit B <b>852</b>, a reception unit B <b>854</b>, and an identification unit B <b>860</b>. In addition, the device B <b>850</b> may further include an operation control unit B <b>856</b>. The device A <b>810</b> and the device B <b>850</b> have configurations corresponding to each other. Therefore, only the device A <b>810</b> will be described in more detail for the sake of convenience of description.

0095The transmission unit A <b>812</b> generates a first micro-current signal that is conveyed by the touch of the touch spot A <b>818</b>. Here, the first micro-current signal includes equipment information of the device A <b>810</b>. The equipment information of the device A <b>810</b> is information used to connect through the communication channel <b>870</b> to the device B <b>850</b>, for example, identification information of the device A <b>810</b>. After that, the transmission unit A <b>812</b> propagates the first micro-current signal to the device B <b>850</b> via the person <b>880</b>.

0096The reception unit A <b>814</b> receives a second micro-current signal from the device B <b>850</b> via the person <b>880</b>. Here, the second micro-current signal includes equipment information of the device B <b>850</b>. The equipment information of the device B <b>850</b> is information used to connect through the communication channel <b>870</b> to the device A <b>810</b>, for example, identification information of the device B <b>850</b>. After that, the reception unit A <b>814</b> detects the equipment information from the second micro-current signal.

0097As shown in <figref idref="DRAWINGS">FIG. 8</figref>, the transmission unit A <b>812</b> and the reception unit A <b>814</b> may transmit the first micro-current signal and receive the second micro-current signal through the same touch spot A <b>818</b>. Alternatively, the transmission unit A <b>812</b> and the reception unit A <b>814</b> may respectively transmit the first micro-current signal and receive the second micro-current signal through different touch spots (not shown) from each other. In this case, the touch spot connecting to the transmission unit A <b>812</b> and the touch spot connecting to the reception unit A <b>814</b> may be adjacent to each other.

0098The identification unit A <b>820</b> identifies the device B <b>850</b> by using the equipment information of the device B <b>850</b> detected by the reception unit A <b>814</b>. Then, the identification unit A <b>820</b> connects the device A <b>810</b> and the device B <b>850</b> to each other via the communication channel <b>870</b>. The communication channel <b>870</b> may be locally connected via a PnP protocol such as a UPnP, and may be a wired or wireless channel. In addition, the communication channel <b>130</b> may be a wireless communication channel, and the wireless communication channel may include one or more of a local area network (LAN), a wireless internet platform for interoperability (WIPI), Bluetooth, an infrared ray, a near field communication (NFC), or Zigbee, etc.

0099The operation control unit A <b>816</b> is connected to a physical operation button (not shown) included in the device A <b>810</b> or an operation button (not shown) displayed on a graphic user interface. For example, when the physical operation button or the operation button displayed on the graphic user interface is pushed, the operation control unit A <b>816</b> controls the transmission unit A <b>812</b> to generate the first micro-current signal and the reception unit A <b>814</b> to receive the second micro-current signal. When the physical operation button or the operation button displayed on the graphic user interface is not pushed, the operation control unit A <b>816</b> controls the transmission unit A <b>812</b> not to generate the first micro-current signal and the reception unit A <b>814</b> to receive the second micro-current signal.

0100Users of the device A <b>810</b> and the device B <b>850</b> may manipulate the device A <b>810</b> and the device B <b>850</b> to be connected only when the physical operation button or the operation button displayed on the graphic user interface in each of the devices is pushed.

0101<figref idref="DRAWINGS">FIGS. 9A</figref>, <b>9</b>B, and <b>9</b>C are diagrams showing examples of touch spots according to exemplary embodiments.

0102<figref idref="DRAWINGS">FIG. 9A</figref> shows an example in which the touch spot is a capacitive button <b>902</b>. The capacitive button <b>902</b> is used as the touch spot for transmitting or receiving the micro-current signal, and at the same time, may be used as an operation button for performing a connecting operation between the devices. For example, the capacitive button <b>902</b> may be connected to a transmission unit <b>904</b>, a reception unit <b>908</b>, and an operation control unit <b>906</b> in a time divisional manner. That is, a switching unit <b>910</b> switches the connection from the capacitive button <b>902</b> to the transmission unit <b>904</b>, the reception unit <b>908</b>, and the operation control unit <b>906</b> at different times. The user of the device starts a connecting operation between the devices by using one button (that is, the capacitive button), and at the same time, transmits and receive the micro-current signals. The transmission unit <b>904</b>, the reception unit <b>908</b>, and the operation control unit <b>906</b> correspond to the transmission unit <b>812</b>, the reception unit <b>814</b>, and the operation control unit <b>816</b> of <figref idref="DRAWINGS">FIG. 8</figref>, and detailed descriptions are not provided here.

0103<figref idref="DRAWINGS">FIGS. 9B and 9C</figref> shows examples when the touch spots are touch electrodes <b>922</b> and <b>944</b>, respectively. The touch electrodes <b>922</b> and <b>944</b> are used to transmit or receive the micro-current signal, and a physical operation button <b>928</b> or an operation button <b>942</b> displayed on graphic user interface is used to start the connecting operation between the devices.

0104<figref idref="DRAWINGS">FIG. 9B</figref> is shows an example in which the touch electrode <b>922</b> is disposed to cover an upper portion of the physical operation button <b>928</b>.

0105The touch electrode <b>922</b> is connected to a transmission unit <b>924</b> and a reception unit <b>926</b>, and the physical operation button <b>928</b> operates an operation control unit <b>934</b> via a conductor <b>930</b> and a terminal <b>932</b> in a touched status. That is, when the touch electrode <b>922</b> is pushed, the physical operation button <b>928</b> is pushed together with the touch electrode <b>922</b> such that the conductor <b>930</b> of the physical operation button <b>928</b> is pressed against the terminals <b>932</b>. Therefore, it is possible to start the connecting operation between the devices and transmit or receive the micro-current signal by touching the touch electrode <b>922</b>. The transmission unit <b>924</b>, the reception unit <b>926</b>, and the operation control unit <b>934</b> correspond to the transmission unit <b>812</b>, the reception unit <b>814</b>, and the operation control unit <b>816</b> of <figref idref="DRAWINGS">FIG. 8</figref>, and detailed descriptions are not provided here.

0106<figref idref="DRAWINGS">FIG. 9C</figref> is an exemplary diagram showing the touch electrode <b>944</b> disposed on a rear surface of a display screen in the device.

0107The touch electrode <b>944</b> is connected to a transmission unit (not shown) and a reception unit (not shown), and an operation button <b>942</b> displayed on the graphic user interface operates an operation control unit (not shown) in a touched status (that is, commanded to operate). Therefore, the operation button <b>942</b> displayed on the graphic user interface is pushed to start the connecting operation between the devices, and the touch electrode <b>944</b> is touched to transmit and receive the micro-current signals through the hand of the user. The transmission unit (not shown), the reception unit (not shown), and the operation control unit (not shown) correspond to the transmission unit <b>812</b>, the reception unit <b>814</b>, and the operation control unit <b>816</b> of <figref idref="DRAWINGS">FIG. 8</figref>, and detailed descriptions are not provided here.

0108<figref idref="DRAWINGS">FIG. 10A</figref> is an exemplary diagram showing an internal structure of the transmission unit <b>812</b> or <b>852</b> shown in <figref idref="DRAWINGS">FIG. 8</figref>.

0109The transmission unit <b>1010</b> corresponding to the transmission unit A <b>812</b> (or the transmission unit B <b>852</b>) includes a signal generation unit <b>1014</b> and a modulation unit <b>1012</b>.

0110The signal generation unit <b>1014</b> generates a signal including device information about the device having a touch spot <b>1002</b> (that is, the device A or device B of <figref idref="DRAWINGS">FIG. 8</figref>). The signal may be, for example, a binary signal. The device information about the device having the touch spot <b>1002</b> is stored in the signal generation unit <b>1014</b> or in an identification unit <b>1020</b>.

0111The modulation unit <b>1012</b> generates a first micro-current signal by modulating the signal generated by the signal generation unit <b>1014</b>, and outputs the first micro-current signal to the touch spot <b>1002</b>. The modulation method may be any modulation method, for example, an on-off keying (OOK) method. In addition, the modulation unit <b>1012</b> may include a band pass filter unit that filters a frequency band.

0112<figref idref="DRAWINGS">FIG. 10B</figref> is an exemplary diagram showing a structure of the reception unit A <b>814</b> (or the reception unit B <b>854</b>) of <figref idref="DRAWINGS">FIG. 8</figref>.

0113The reception unit <b>1040</b> corresponding to the reception unit A <b>814</b> (or the reception unit B <b>854</b>) includes a filter unit <b>1042</b>, an amplification unit <b>1044</b>, and a demodulation unit <b>1046</b>.

0114The filter unit <b>1042</b> removes a noise component from a second micro-current signal received through the touch spot <b>1032</b>. Since the second micro-current signal is transmitted via a human being, the second micro-current signal generally include the noise component.

0115The amplification unit <b>1044</b> amplifies the signal output from the filter unit <b>1042</b>.

0116The demodulation unit <b>1046</b> demodulates the signal output from the amplification unit <b>1044</b> to detect the signal including the information about an external device (not shown). The demodulation method may vary depending on modulation method used.

0117<figref idref="DRAWINGS">FIG. 5</figref> is a flowchart illustrating a touch-screen based device identification method for a touch screen device according to an exemplary embodiment.

0118Referring to <figref idref="DRAWINGS">FIG. 5</figref>, in operation <b>510</b>, the touch screen device propagates a micro-current signal, including a scan frequency component, induced by touching a touch screen surface to an external device via a person. The external device may be, for example, a cellular phone, a digital camera, a camcorder, a PDA, an MP3 player, or a PMP, etc. The touch screen device may temporarily change a scan frequency of a micro-current induced by touching the touch screen surface.

0119In operation <b>520</b>, receives information about the scan frequency component detected by the external device and an ID of the external device from the external device through a communication channel. The communication channel may be a wired or wireless channel using a PnP protocol such as an UPnP protocol.

0120In operation <b>530</b>, the touch screen device identifies the external device by using the received information about the scan frequency component and the received ID of the external device. For example, the touch screen device may determine that the touch screen is connected with the external device having the received ID if the received information about the scan frequency component is the same as a scan frequency component of the signal induced by a touch.

0121In operation <b>540</b>, the touch screen device calculates coordinates of the touch screen surface that is touched.

0122In operation <b>550</b>, the touch screen device maps the external device identified in operation <b>530</b> to the calculated coordinates of the touch screen surface that is touched.

0123In addition, the touch screen device may calculate first coordinates of the touched point on the touch screen surface, and then, maps the external device to the first coordinates.

0124In addition, the touch screen device may execute user verification services that allow the external device to access the touch screen device or to access the object displayed on the first coordinates of the touch screen device using the user verification information stored in the external device.

0125Also, as described above, the external device may be another touch screen device in addition to the touch screen device. In this case, the touch screen device calculates first coordinates of the touched point on the touch screen surface, and then, performs a mapping operation of the calculated first coordinates to second coordinates that represent the touched point on the touch screen surface of the other touch screen device through the communication channel.

0126In addition, the touch screen device may transmit a control signal, which allows the object represented at the first coordinates to be represented at the second coordinates, to the other touch screen device or may receive the control signal from the other touch screen device.

0127<figref idref="DRAWINGS">FIG. 6</figref> is a flowchart illustrating a device information provision method for an external device according to another exemplary embodiment.

0128Referring to <figref idref="DRAWINGS">FIG. 6</figref>, in operation <b>610</b>, the external device detects a scan frequency component from a micro-current signal including a scan frequency component induced by touching a touch screen surface. For example, the external device may perform band-pass filtering on the micro-current signal by using a scan frequency as a center frequency and perform tone-decoding on the band-pass filtered signal. The external device may be, for example, a cellular phone, a digital camera, a camcorder, a PDA, an MP3 player, or a PMP, etc.

0129In operation <b>620</b>, the external device generates information about the scan frequency component and ID information of the external device that has received the micro-current signal.

0130In operation <b>630</b>, the external device transmits the information about the scan frequency component and the ID information to the touch screen device through a communication channel. The communication channel may be a wired or wireless channel using a PnP protocol such as an UPnP protocol.

0131When the scan frequency of a micro-current induced by touching the touch screen surface is temporarily changed by the touch screen device, the external device may repetitively perform operations <b>610</b> through <b>630</b>.

0132In addition, when the external device is identified by the touch screen device and is mapped on the first coordinates that represent the touched point on the touch screen surface in the touch screen device, the external device may access the touch screen device using the user verification information stored therein or may execute a user verification process for accessing the object displayed at the first coordinates of the touch screen device.

0133In addition, the external device may be another touch screen device in addition to the touch screen device. In this case, the external device calculates second coordinates that represent the touched point of the touch screen surface of the external device, and may perform a mapping operation of the second coordinates to the first coordinates of the touch screen device.

0134In addition, for example, the external device may transmit a control signal, which allows the object displayed at the first coordinates to be displayed at the second coordinates, to the touch screen device or may receive the control signal from the touch screen device.

0135<figref idref="DRAWINGS">FIG. 11</figref> is a flowchart illustrating an external device identification method in a device including a touch spot according to another exemplary embodiment.

0136In operation S<b>1102</b>, the device including the touch spot generates a first micro-current signal that is induced when the touch spot is touched and includes device information about the device including the touch spot.

0137The touch spot may be a touch electrode or a capacitor button, for example. The touch electrode may be disposed to cover an upper portion of a physical operation button (see <figref idref="DRAWINGS">FIG. 9B</figref>). Alternatively, the touch electrode may be disposed on a rear surface of a display screen including the touch spot (see <figref idref="DRAWINGS">FIG. 9C</figref>).

0138The capacitive button propagates the first micro-current signal to the external device in a time-divisional manner and receives the second micro-current signal from the external device, and may be used to control the generation of the first micro-current signal and receipt of the second micro-current signal (see <figref idref="DRAWINGS">FIG. 9A</figref>).

0139In operation S<b>1104</b>, the device including the touch spot propagates the first micro-current signal to the external device via the human being. For example, the device including the touch spot may generate a binary signal including the device information about the device including the touch spot and may generate the first micro-current signal by modulating the binary signal, and may output the generated first micro-current signal to the touch spot.

0140In operation S<b>1106</b>, the device including the touch spot receives the second micro-current signal including device information about the external device via the human being from the external device. The second micro-current signal may be received through the same touch spot as or different touch spot from that of the first micro-current signal.

0141In operation S<b>1108</b>, the device including the touch spot detects the device information of the external device from the second micro-current signal. For example, the device including the touch spot removes a noise component from the second micro-current signal, amplifies the signal from which the noise component is removed, and demodulates the amplified signal to detect the signal including the device information about the external device.

0142In operation S<b>1110</b>, the device including the touch spot identifies the external device by using the detected device information about the external device.

0143In operation S<b>1112</b>, the device including the touch spot connects to the external device through the communication channel.

0144In addition, the device including the touch spot may control the device to generate the first micro-current signal and receive the second micro-current signal when the physical operation button or the operation button displayed on the graphic user interface is pushed.

0145A program for executing a touch-screen based device identification method and an external device identification method in a device including touch spot according to the exemplary embodiments can be embodied as a computer-readable code on a computer-readable recording medium. The computer-readable recording medium may be a computer readable storage medium such as any data storage device that can store data which can be thereafter read by a computer system. Examples of computer-readable storage media include read-only memory (ROM), random-access memory (RAM), CD-ROMs, magnetic tapes, floppy disks, and optical data storage devices. Alternatively, the computer readable recording medium may be a computer readable transmission medium such as a carrier wave. The computer-readable recording medium can be distributed over network of coupled computer systems so that the computer-readable code is stored and executed in a decentralized fashion.

0146While exemplary embodiments been particularly shown and described, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the inventive concept as defined by the following claims.